Jehu w



(No Model.)

J. W. DAVIS. DOOR SPRING.

No. 403,922. Patented May 28. 1889..

4 1 UNITED STATES PATENT O FICE;

JEHU W. DAVIS, OF LE ROY, KANSAS, ASSIGNOR OF TWO-THIRDS TO EDWIN B. FOSTER AND JOHN WV. LEEDY, OF SAME PLACE.

DOOR-SPRING.

SPECIFICATION formingpart of Letters Patent No. 403,922, dated May 28, 1889. Application filed February 15, 1889. Serial No. 300,023. (No model.)

To all whom it may concern.-

Be it known that I, J EHU WV. DAVIS, a citizen of the United States, residing at Le Boy, in the county of Coffey and State of Kansas,

5 have invented new and useful Improvements in Self-Closing Door-Sprin gs, of which the following is a specification.

The invention relates to improvements in self-closing door-springs; and it consists in a certain novel construction and combination of devices, fully described hereinafter in connection with the accompanying drawings, and specifically pointed out in the appended claims.

In the drawings, Figure 1 is a perspective View of the improved door-spring applied in its operative position to a door. Fig. 2 is a horizontal sectional view through the hinged edge of the door, the casing, and the doorspring. Fig. 3 is a vertical central sectional View of the spring-casing, showing the disposition of the spring therein. Fig. 4 is a detail View of the hinge to which the door-spring is attached.

Referring by letter to the drawings, A designates a door, which is hinged in the ordinary manner to the door-casing B, and the central knuckle of one of the hinges C is cut away slightly to permit the segmental gear-wheel D to be mounted on the pintle of the said hinge. The front end of the gear-wheel is provided with a small ear, which is attached to the front side of the door, and the rear end thereof is arranged adjacent to the hinged edge of the door. The door-casin g is horizontally slotted, as seen at F, and as the door is opened or closed the gear-wheel operates in this slot.

- G represents a spring-casing comprising the top plate, H, and the annular rim I, which is integral with the top plate, and the loose bot tom plate, H, which bears against the lower edge of the annular side. Vertical screws K K extend through perforations in the lower plate and engage threaded sockets in the lugs kof the annular rim of the casing. The lower plate, H, is provided in its upper surface with an annular groove, h, which receives the lower edge of the annular rim, and a portion of the lower edge of the side is cut away to form a slot, i, through which the large gear-wheel projects.

L represents a spiral spring, which is arranged in the spring-casing, and is provided with a vertical arbor, M, mounted in registerin g-bearin gs in the top and bottom plates, one end of said arbor being squared to enable the spring to be tightened. A pinion, N, is formed on one end of this arbor within the casing and meshes with the gear-wheel which is attached to and swings with the door.

The top and bottom plates of the spring-easing are provided with integral arms 0 O,which are also mounted on the pintle of the hinge O, the central knuckle of the latter being cut away to receive the said arms.

The operation of the improved door-spring will be obvious from x the above description. As the door is swung open, the gear-wheel which swings therewith operates upon the pinion and winds the spiral spring, and when the door is released the said spring unwinds, and thereby reverses the operation and closes the door. The wider the door is swung open the tighter the spring is wound, and therefore the more power it receives. As the door closes, 7 5 the greatest power of the spring is applied at first, and as the door approaches the closed position the power of the spring diminishes. Therefore the door is closed gradually and noiselessly. If the door which is to be op erated is unusually heavy, the spring may be slightly tightened, as above described.

From the above description it will be seen that the improved door-spring is not attached directly to either the door or the door-casing, and therefore they are not marred. The hinge O is of the ordinary or well-known construction, except that its intermediate or movable knuckle is slightly cut away to expose a portion of the pintle sufficient to receive the gear- 0 wheel and the arms of the plates.

A further advantage of the improved doorspring is that it operates directly upon the door (to close it) when the latter is open beyond the perpendicular position.

The main feature of my invention is that the gear-wheel is connected directly to the pintle of the door-hinge, thus utilizing the latter as a means of connection for the spring closing device.

Having thus described the invention, I claim-- of the hinge, and the spring-actuated pinion N within said casing, meshing with said segmental gear, the whole operating substantially as described. In testimony that I claim the foregoing as my own I have hereto affixed my signature in presence of two Witnesses.

JEHU W. DAVIS. WVitnesses:

J. W. LEEDY, EDWIN B. FOSTER. 

